1. Technical Field of the Invention
The present invention relates, generally, to an acceleration limit switch.
More particularly, the present invention relates to an acceleration limit switch having a ball-shaped inertia body made of a ferromagnetic material. The body of the switch is maintained in a resting position by a permanent magnet opposed on a printed circuit board by two contact elements symmetrically engaging each other.
2. Description of the Prior Art
Acceleration limit switches are generally known to the prior art with one such switch being disclosed by Federal Republic of Germany Patent No. 30 22 878. The acceleration limit switch disclosed in this prior art reference consists of a housing having a permanent magnet, an inertia body supported by said permanent magnet, and a contact system. The contact system has a conductive mat and a printed circuit board with conducting paths engaging one another in the manner of a comb. The printed circuit board and the diaphragm are supported by a cover projecting across the latter on top; said cover having bores for receiving the connection pins extending therethrough.
Within the zone of the jacket, the cylindrical housing has a groove extending all around, in which an O-ring is inserted. When the cover is slipped on, its collar seals the interior space of the switch with deformation of the O-ring.
The prior art acceleration limit switch, which has been successfully used for many years, requires a molded, and therefore expensive, contact mat, a printed circuit board with pins soldered into the latter, and a cover provided with a collar. The type of sealing used requires very small tolerances for the housing and the cover.